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|
Attributes | |
ACN | 734145 |
Time | |
Date | 200704 |
Place | |
Locale Reference | navaid : tfd.vortac |
State Reference | AZ |
Environment | |
Flight Conditions | VMC |
Aircraft 1 | |
Controlling Facilities | tracon : sju.tracon |
Operator | common carrier : air carrier |
Make Model Name | A320 |
Operating Under FAR Part | Part 121 |
Flight Phase | climbout : intermediate altitude |
Flight Plan | IFR |
Person 1 | |
Affiliation | company : air carrier |
Function | flight crew : captain oversight : pic |
Qualification | pilot : atp |
ASRS Report | 734145 |
Person 2 | |
Affiliation | government : faa |
Function | controller : radar |
Events | |
Anomaly | other anomaly other other spatial deviation |
Independent Detector | atc equipment other atc equipment : radar other controllera |
Resolutory Action | controller : issued alert flight crew : overrode automation |
Consequence | faa : reviewed incident with flight crew |
Supplementary | |
Problem Areas | Aircraft |
Primary Problem | Aircraft |
Narrative:
This event occurred because ATC expects us to fly closer to the center of the airway than required by the aim and because we chose to allow the aircraft to fly to the limits of the aim. ATC kept us on the 100 degree heading for quite a distance then cleared us direct tfd as filed. This gave us about a 90 degree turn over tfd to the 121 degree outbound to tus. I was concerned about the wide turn the automation was planning to make at tfd; as I recalled there were problems with the old goffs intersection out of las yrs ago. I mentioned this to the first officer and then had a closer look on the navigation display; which indicated that we would remain just within 4 mi of the airway in the turn. About 7 mi from tfd; which is a mi or two after the A320 started the turn; ATC contacted us to ask where we were going. We repeated our clearance and asked them to verify. ATC pointed out that we were already starting our turn; which we knew to be normal for the airbus; but didn't clearly spell out what their concern was. Rather than get in an argument; I asked for a heading. ATC refused and stated they wanted us to fly our clearance and to expedite our climb for traffic. At this point we were still within the airway. We complied with the climb and guessing the wide turn was the issue; we put the aircraft on a heading to tfd and then manually entered a heading for the outbound. Once outbound; we selected managed navigation. We are guessing that this was the problem; since ATC never came right out and said what they wanted or needed for separation. This is one of those standard airbus 'issues.' of course in the future; when making a turn on an airway greater than 70 degrees; or so; I'll use the heading mode. This is the main change to be made. ATC should be more aware of this issue over tfd the way they are out by lidat. More importantly; and I've seen this in many instances; it is very important that when an aircraft is going somewhere a controller does not want it to go; that the controller get the airplane where it needs to be using unambiguous headings and altitudes. Then; after letting the crew know they are out of the conflict; converse about the misunderstanding. What happened in this case is we were told to get back on our clearance. We thought; and somewhat rightly so; that we were on it; and we had to make a number of xmissions back and forth to make sure of what the controller wanted. This was a lot of stress and distraction in a tight situation.
Original NASA ASRS Text
Title: ZAB CONTROLLER QUESTIONS A320 FLT CREW ABOUT THEIR EARLY TURN APPROACHING A NAVAID TO THE OUT BOUND LEG WITH A 90 DEGREE HEADING CHANGE.
Narrative: THIS EVENT OCCURRED BECAUSE ATC EXPECTS US TO FLY CLOSER TO THE CTR OF THE AIRWAY THAN REQUIRED BY THE AIM AND BECAUSE WE CHOSE TO ALLOW THE ACFT TO FLY TO THE LIMITS OF THE AIM. ATC KEPT US ON THE 100 DEG HDG FOR QUITE A DISTANCE THEN CLRED US DIRECT TFD AS FILED. THIS GAVE US ABOUT A 90 DEG TURN OVER TFD TO THE 121 DEG OUTBOUND TO TUS. I WAS CONCERNED ABOUT THE WIDE TURN THE AUTOMATION WAS PLANNING TO MAKE AT TFD; AS I RECALLED THERE WERE PROBS WITH THE OLD GOFFS INTXN OUT OF LAS YRS AGO. I MENTIONED THIS TO THE FO AND THEN HAD A CLOSER LOOK ON THE NAV DISPLAY; WHICH INDICATED THAT WE WOULD REMAIN JUST WITHIN 4 MI OF THE AIRWAY IN THE TURN. ABOUT 7 MI FROM TFD; WHICH IS A MI OR TWO AFTER THE A320 STARTED THE TURN; ATC CONTACTED US TO ASK WHERE WE WERE GOING. WE REPEATED OUR CLRNC AND ASKED THEM TO VERIFY. ATC POINTED OUT THAT WE WERE ALREADY STARTING OUR TURN; WHICH WE KNEW TO BE NORMAL FOR THE AIRBUS; BUT DIDN'T CLRLY SPELL OUT WHAT THEIR CONCERN WAS. RATHER THAN GET IN AN ARGUMENT; I ASKED FOR A HDG. ATC REFUSED AND STATED THEY WANTED US TO FLY OUR CLRNC AND TO EXPEDITE OUR CLB FOR TFC. AT THIS POINT WE WERE STILL WITHIN THE AIRWAY. WE COMPLIED WITH THE CLB AND GUESSING THE WIDE TURN WAS THE ISSUE; WE PUT THE ACFT ON A HDG TO TFD AND THEN MANUALLY ENTERED A HDG FOR THE OUTBOUND. ONCE OUTBOUND; WE SELECTED MANAGED NAV. WE ARE GUESSING THAT THIS WAS THE PROB; SINCE ATC NEVER CAME RIGHT OUT AND SAID WHAT THEY WANTED OR NEEDED FOR SEPARATION. THIS IS ONE OF THOSE STANDARD AIRBUS 'ISSUES.' OF COURSE IN THE FUTURE; WHEN MAKING A TURN ON AN AIRWAY GREATER THAN 70 DEGS; OR SO; I'LL USE THE HDG MODE. THIS IS THE MAIN CHANGE TO BE MADE. ATC SHOULD BE MORE AWARE OF THIS ISSUE OVER TFD THE WAY THEY ARE OUT BY LIDAT. MORE IMPORTANTLY; AND I'VE SEEN THIS IN MANY INSTANCES; IT IS VERY IMPORTANT THAT WHEN AN ACFT IS GOING SOMEWHERE A CTLR DOES NOT WANT IT TO GO; THAT THE CTLR GET THE AIRPLANE WHERE IT NEEDS TO BE USING UNAMBIGUOUS HDGS AND ALTS. THEN; AFTER LETTING THE CREW KNOW THEY ARE OUT OF THE CONFLICT; CONVERSE ABOUT THE MISUNDERSTANDING. WHAT HAPPENED IN THIS CASE IS WE WERE TOLD TO GET BACK ON OUR CLRNC. WE THOUGHT; AND SOMEWHAT RIGHTLY SO; THAT WE WERE ON IT; AND WE HAD TO MAKE A NUMBER OF XMISSIONS BACK AND FORTH TO MAKE SURE OF WHAT THE CTLR WANTED. THIS WAS A LOT OF STRESS AND DISTR IN A TIGHT SITUATION.
Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.